Spring-tooth harrow



(No Model.)

P. J. NORTH & A. F. MOLITOR.

SPRING TOOTH HARROW.

PatentedSep't. 2, 1890.

UNITED STATES PATENT OFF FORD J. NORTH AND AARON FRED MOLITOR, OFLANSING, MICHIGAN.

SPRING-TOOTH HARROW.

SPECIFICATION forming part of Letters Patent No. 435,706, datedSeptember 2, 1890.

Application filed :Tuly 1, 1889 Serial No. 316,182. (No model.)

To all whom it may concern:

Be it known that we, FORD J. NORTH and AARON FRED MOLITOR, citizens ofthe United States, residing at Lansing, in the county of Inghann andState of Michigan, have invented certain new and useful Improvements inSpring=Tooth Harrows, of which the following is a specification,reference being had therein to the accompanying drawings.

This invention relates to new and useful improvements in spring-toothharrows.

The object of the invention is to construct a harrow with a tubularframe and means for securing together the sections of the frame andattaching the teeth thereto, whereby alighter, stronger, and moreserviceable harrow is made than is now known.

In the drawings which accompany this specification, Figure l is a planview of our improved harrow with the teeth attached. Fig. 2 is anenlarged plan view of the connection of one of the teeth. Fig. 3 is across-section on line 00 x in Fig. 2. Fig. at is a section on line y yin Fig. 2.

A are the bars composing the frame of the harrow. These bars are made ofpiping, bending them in a horizontal plane into bends B, giving them aserpentine form, and assembling them together with the points of thebends of adjoining bars approaching each other and secured in positionby means of clips G, the bolts E of which pass through suitableapertures D in the bars. The central bars 0 are provided with suitableapertures to receive a bolt C to secure the two halves of the frametogether. The clip-bolts E are made suitably long to pass through thebars, the clipplates, and the nuts E; also, to leave the space F betweenthe lower clipplate and the bars in which to insert the curved end ofthe tooth G. The two upward bends of the barrow-tooth are wedged betweenthe sides of the bars, which at their points of connection form adouble-wedgeshaped bearing, as shown in Figs. 2 and at. It is evidentthat the spring-tooth has bearing at the points a and I) only, and intight-- ening up the nuts E the bend c of the spring is put undercompression, and its resiliency tends at all times to hold the nutsagainst accidental displacement. The bearingsct and 17, holding thetooth between, assist in making the frame perfectly rigid, as the barsof the frame cannot have an end motion upon each other without lesseningthe distance between the bends, which is impossible on ac= count of theintermediate section of the spring. No extra castings are required toattach the spring to the frame, as the frame itself by the bendsdescribed, with the addition of the clips, form the necessary bearingfor the spring-tooth. The bolts 0'', being arranged in line, make apivotal connection between the two halves of the harrow. II is asuitable draft attachment. With this con struction it simply requiresthe loosening of the nuts E to put the harrow in a knockdown condition.

In use there are no parts to rattle, as all the clips and bolts are heldfirmly in place by the clamping of the clips upon the bond 0 of thespring, as before described. It is evident that it is easier to bend thebars into a curve than into a right-angled bend, and the curve gives abetter result in construction.

What we claim as our invention is- 1. In a harrow, the combination ofsets of serpentine bars having the points of the bends approaching eachother and spring teeth held at two points in their length directlybetween the bends of the bars and clamped by direct contact between theteeth and the surfaces of two contiguous bends of the bars, withhorizontal clips having vertical bolts to clamp the teeth and barstogether, substantially as described.

2. In a harrow, the combination, with the tubular bars A, having bendsB, assembled together with the points of the bends approaching eachother, of the clips 0, whose bolts E pass through the apertures D in thebars, the space F between the lower clipplate and the bars, and thespring-teeth G, clamped in the space F, substantially as described.

In a harrow, the combination of tubular bars having bends assembledtogether connected by clips with the points of the bends approachingeach other and forming a tures, in presence of two witnesses, this 29thdouble wedge-shaped bearing for the springday of May, 1889. teeth andthe bends in said spring-teeth, the parts being arranged and constructedto 5 operate substantially as and for .the purpose described.

- In testimony whereof We afiix our signa- FORD J. NORTH.

A. FRED MOLITOR. Witnesses:

A. F. PORTER, W. L. GROVE.

